1. Field of the Invention
The invention relates generally to the field of data networking. More particularly, the invention relates to distributing network synchronization timing in a packet switched local area network.
2. Discussion of the Related Art
The explosive growth of the Internet and the penchant for applying packetized transmission methods for all forms of information traffic has created the need for providing adequate synchronization down to the desk-top level. Inherently, packetized transmission schemes are not geared to transmit time-base information; packets enter the “cloud” and are carried over diverse routes to the destination where they may arrive out of order and with varying delays. In contrast, circuit-switched traffic maintains a given transmission path, the transmission delays are unknown but constant, and sequencing is maintained down to the bit level. Thus, in a packet-switched environment, there is the compelling need to provide synchronization at the entry/egress nodes of the “cloud”; in a general sense these are the “absolute” end-points comprising desk-top PCs and other “Internet Appliances” (including, but not limited, to IP-ready telephones and IP-ready streaming video players/recorders).
The ubiquitous interconnection mechanism associated with Personal Computers (PCs), desktop workstations, etc., is Ethernet. Furthermore, the most common form of Ethernet deployed is over twisted pair cable, namely, 10BaseT and 100BaseT (the 10 and 100 refer to 10 Mbps and 100 Mbps, respectively). For specificity, we shall concentrate here on 10BaseT though extensions of the concepts to 100BaseT, other forms of Ethernet, and other forms of LANs, such as Token Ring, are quite straightforward.
Heretofore, the requirement(s) of providing adequate synchronization down to desk-top level referred to above has not been fully met. What is needed is a solution that addresses this requirement.